1. Field of the Invention
The present invention relates to an engine appropriate for use, for example, on motorcycles, and more particularly to an engine with a transmission case housing a V-belt type of continuously variable transmission (CVT) on one side in the crankshaft direction of the engine case.
2. Technical Background
Some of the engines for use on motorcycles, for example, are provided with a CVT located on the axially outer side of the engine case and housing a V-belt type of CVT mechanism in a transmission case. In the engine described as above, since the transmission case occupies one side of the engine case, a problem of increased lateral and longitudinal engine dimensions may occur depending on the arrangement of engine accessories such as parts constituting the lubricating and starting systems.
A conventional type of engine with a V-belt type of CVT has an arrangement of the oil filter, for example, constituting the lubricating system where the oil filter is removably attached to and protruding on the side wall of the engine case. A conventional arrangement of the kick shaft constituting the starting system is that the kick shaft is located on the opposite side of the transmission case and between a drive and a driven pulley. However, the arrangement of the oil filter described above has a problem of increased lateral and longitudinal engine dimensions since the oil filter protrudes forward from the front wall of the engine case or laterally from the side wall.
Additionally, the arrangement of the kick shaft described above has a problem of increased lateral engine dimension, because the mechanism for transmitting the rotation of the kick shaft to the crankshaft is disposed on the outer side of the generator of the engine case in the lateral direction.
A feature of the present invention made in view of the situations with the prior art described above is to provide an engine capable of avoiding an increase in engine size in the longitudinal and lateral directions in case the transmission case is provided on one side of the engine case.